package com.hmdp.utils;

import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.format.annotation.DateTimeFormat;
import org.springframework.stereotype.Component;

import javax.annotation.Resource;
import java.time.LocalDateTime;
import java.time.ZoneOffset;
import java.time.format.DateTimeFormatter;

/**
 * @author liuchun
 * Redis实现全局唯一ID
 */
@Component
public class RedisIdWorker {
    //开始时间戳
    private static final long BEGIN_TIMESTAMP = 1710799478L;

    //序列号位数
    private static final int COUNT_BITS = 32;

    @Resource
    private StringRedisTemplate stringRedisTemplate;



    public long nextId(String keyPrefix){
        //生成时间戳
        LocalDateTime now = LocalDateTime.now();
        long nowSecond = now.toEpochSecond(ZoneOffset.UTC);
        long timeStamp = nowSecond - BEGIN_TIMESTAMP;

        //生成序列号
        String date = now.format(DateTimeFormatter.ofPattern("yyyy:MM:DD"));
        //获取当天日期，自增长
        long count = stringRedisTemplate.opsForValue().increment("icr" + keyPrefix +":" + date);

        //拼接返回
        return timeStamp << COUNT_BITS | count;
    }




//    public static void main(String[] args) {
//        LocalDateTime now = LocalDateTime.now();
//        long second = now.toEpochSecond(ZoneOffset.UTC);
//        System.out.println("second = " + second);
//    }
}
